Recently, as trends in telecommunications rapidly move from analog toward broadband operations, the variety of and speed by which features are offered by mobile telecommunication devices continues to significantly improve. The demands placed on today's mobile devices often require total performance with minimal latency while establishing multimedia communications sessions, instant messaging, file transfer, and push to talk sessions for law enforcement and public safety applications among others.
It is desired that broadband public safety devices support multiple access networks simultaneously such as, among others, Long Term Evolution (LTE) systems, Wireless Local Area Network (WLAN) systems, Code Division Multiple Access (CDMA) systems, etc. In one particular example, LTE provides end-to end Internet Protocol (IP) service delivery of media to mobile telephone networks and is quickly emerging as the preferred standard for radio technologies within the United States for commercial carriers as well as public safety, security, and defense agencies alike.
Illustratively, in the area of public safety, security, and defense, it is often vital to quickly move first responders that perform a wide range of mission critical operations to a particular incident across a variety of radio access networks to the locale of the incident. However, while exposed to a variety of radio access network systems, many times the User Equipment (UE) assigned to each responder encounters discrepancies in network service that often unacceptably compromises the responder's ability to conduct mission critical operations with minimal latency. For example, often a UE device will appear to the responder as if device operations are stalled or “hanging” while the device searches for a suitable radio access network for service attachment.
Unfortunately, current UE devices are commonly equipped with predetermined static configurations for attaching to subsequent radio access networks that fail to identify the current overall status of that targeted radio access network, including for example such factors as if a target network for future attachment is overloaded, impaired, or will ultimately reject the UE device as having insufficient admission priority. In this disclosure and appended claims the term “target network” means a neighboring candidate network for possible attachment by a UE device upon detachment from its active access network.
More particularly, 3GPP (3rd Generation Partnership Project) specification 31.102 in sections 4.2.53 and 4.2.54 defines behaviors of a USIM application for mobile devices (user equipment). For example, the document contains options for attachment priority; either manual (end-user selection) or automatic (attachment selected by device) which use a “PLMN selector with Access Technology”. For automatic attachment selection, the USIM contains a prioritized list of PLMN ID (public land mobile network identifier) with a radio access technology identifier (e.g. E-UTRAN, cdma200 HRPD, GSM, etc.). The device iterates through the list, attempting to attach to each access network and locate an access network supporting its preferred core network, which is identified by the PLMN ID. Such a method is an efficient and not suited to certain implementation scenarios, such as in the realm of public safety and mission critical applications.
Thus, there exists a need for methods for intelligent network selection that address shortcomings of network selection based on predetermined static configuration.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments. In addition, the description and drawings do not necessarily require the order illustrated. It will be further appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required.
Apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the various embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Thus, it will be appreciated that for simplicity and clarity of illustration, common and well-understood elements that are useful or necessary in a commercially feasible embodiment may not be depicted in order to facilitate a less obstructed view of these various embodiments.